/*
silverPDF is sponsored by Aleyant Systems (http://www.aleyant.com)

silverPDF is based on PdfSharp (http://www.pdfsharp.net) and iTextSharp (http://itextsharp.sourceforge.net)

Developers: Ai_boy (aka Oleksii Okhrymenko)

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:

The above information and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR SPONSORS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

*/
#region PDFsharp - A .NET library for processing PDF
//
// Authors:
//   Stefan Lange (mailto:Stefan.Lange@pdfsharp.com)
//
// Copyright (c) 2005-2008 empira Software GmbH, Cologne (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.
#endregion

using System;
using System.Diagnostics;
using System.Globalization;
using System.Runtime.InteropServices;
using System.Text;
#if GDI
using System.Drawing;
using System.Drawing.Drawing2D;
#endif
#if WPF
using System.Windows;
using System.Windows.Media;
#endif
using PdfSharp.Pdf.Internal;
using PdfSharp.Drawing;

namespace PdfSharp.Fonts.TrueType
{
  /// <summary>
  /// The TrueType font desriptor.
  /// </summary>
  internal sealed class TrueTypeDescriptor : FontDescriptor
  {
    //#if 
    public TrueTypeDescriptor(XFont font, XPdfFontOptions options, XPrivateFontCollection privateFontCollection)
    {
      ///try
      ///{
        this.fontData = new FontData(font, options);
        this.fontName = font.Name;
        Initialize();
      ///}
      ///catch (Exception ex)
      ///{
      ///  throw ex;
      ///}
    }
    //#endif

    //#if WPF
    //    public TrueTypeDescriptor(XFont font, XPdfFontOptions options)
    //    {
    //      try
    //      {
    //        this.fontData = new FontData(font, options);
    //        this.fontName = font.Name;
    //        Initialize();
    //      }
    //      catch (Exception ex)
    //      {
    //        throw ex;
    //      }
    //    }
    //#endif

    //internal TrueTypeDescriptor(FontSelector selector)
    //{
    //  throw new NotImplementedException("TrueTypeDescriptor(FontSelector selector)");
    //}

    internal TrueTypeDescriptor(XFont font,
      XPrivateFontCollection privateFontCollection)
      : this(font, font.PdfOptions, privateFontCollection)
    { }

    internal TrueTypeDescriptor(string idName, byte[] fontData)
    {
      try
      {
        this.fontData = new FontData(fontData);
        // Try to get real name form name table
        if (idName.Contains("XPS-Font-") && this.fontData.name != null && this.fontData.name.Name.Length != 0)
        {
          string tag = String.Empty;
          if (idName.IndexOf('+') == 6)
            tag = idName.Substring(0, 6);
          idName = tag + "+" + this.fontData.name.Name;
          if (this.fontData.name.Style.Length != 0)
            idName += "," + this.fontData.name.Style;
          idName = idName.Replace(" ", "");
        }
        this.fontName = idName;
        Initialize();
      }
      catch (Exception ex)
      {
        throw ex;
      }
    }

    internal FontData fontData;

    void Initialize()
    {
      bool embeddingRestricted = this.fontData.os2.fsType == 0x0002;

      //this.fontName = image.n
      this.italicAngle = this.fontData.post.italicAngle;

      this.xMin = this.fontData.head.xMin;
      this.yMin = this.fontData.head.yMin;
      this.xMax = this.fontData.head.xMax;
      this.yMax = this.fontData.head.yMax;

      this.underlinePosition = this.fontData.post.underlinePosition;
      this.underlineThickness = this.fontData.post.underlineThickness;
      this.strikeoutPosition = this.fontData.os2.yStrikeoutPosition;
      this.strikeoutSize = this.fontData.os2.yStrikeoutSize;

      // No documetation found how to get the set vertical stems width from the
      // TrueType tables.
      // The following formula comes from PDFlib Lite source code. Acrobat 5.0 sets
      // /StemV to 0 always. I think the value doesn't matter.
      //float weight = (float)(this.image.os2.usWeightClass / 65.0f);
      //this.stemV = (int)(50 + weight * weight);  // MAGIC
      this.stemV = 0;

      // PDFlib states that some Apple fonts miss the OS/2 table.
      Debug.Assert(fontData.os2 != null, "TrueType font has no OS/2 table.");

      this.unitsPerEm = fontData.head.unitsPerEm;

      // PDFlib takes sTypoAscender and sTypoDescender from OS/2 tabel, but GDI+ uses usWinAscent and usWinDescent
      if (fontData.os2.sTypoAscender != 0)
        this.ascender = fontData.os2.usWinAscent;
      else
        this.ascender = fontData.hhea.ascender;
      Debug.Assert(this.ascender > 0, "PDFsharp internal: Ascender should be greater than 0.");

      if (fontData.os2.sTypoDescender != 0)
      {
        this.descender = fontData.os2.usWinDescent;
        Debug.Assert(this.descender > 0, "PDFsharp internal: Font with non positive ascender value found.");
#if true_
        Debug.WriteLine(String.Format(CultureInfo.InvariantCulture,
          "os2.usWinDescent={0}, hhea.descender={1}, os2.sTypoDescender={2}", fontData.os2.usWinDescent, fontData.hhea.descender, fontData.os2.sTypoDescender));
#endif
        // Force sign from hhea.descender
        // TODO:
        this.descender = Math.Abs(this.descender) * Math.Sign(fontData.hhea.descender);
      }
      else
        this.descender = fontData.hhea.descender;
      Debug.Assert(this.descender < 0, "PDFsharp internal: Ascender should be less than 0.");

      this.leading = fontData.hhea.lineGap;

      // sCapHeight and sxHeight are only valid if version >= 2
      if (fontData.os2.version >= 2 && fontData.os2.sCapHeight != 0)
        this.capHeight = fontData.os2.sCapHeight;
      else
        this.capHeight = fontData.hhea.ascender;

      if (fontData.os2.version >= 2 && fontData.os2.sxHeight != 0)
        this.xHeight = fontData.os2.sxHeight;
      else
        this.xHeight = (int)(0.66f * this.ascender);

      //this.flags = this.image.
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
      //Encoding ansi = PdfEncoders.WinAnsiEncoding; // System.Text.Encoding.Default;
      //Encoding ansi = System.Text.Encoding.Unicode;
      Encoding ansi = new ASCIIEncoding();
//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
      Encoding unicode = System.Text.Encoding.Unicode;
      byte[] bytes = new byte[256];

      bool symbol = this.fontData.cmap.symbol;
      this.widths = new int[256];
      for (int idx = 0; idx < 256; idx++)
      {
        bytes[idx] = (byte)idx;
        // PDFlib handles some font flaws here...
        // We wait for bug reports.

        char ch = (char)idx;
        string s = ansi.GetString(bytes, idx, 1);
        if (s.Length != 0)
        {
          if (s[0] != ch)
            ch = s[0];
        }
#if DEBUG
        if (idx == (int)'S')
          GetType();
#endif
        int glyphIndex;
        if (symbol)
        {
          glyphIndex = idx + (this.fontData.os2.usFirstCharIndex & 0xFF00);
          glyphIndex = CharCodeToGlyphIndex((char)glyphIndex);
        }
        else
        {
          //Debug.Assert(idx + (this.fontData.os2.usFirstCharIndex & 0xFF00) == idx);
          //glyphIndex = CharCodeToGlyphIndex((char)idx);
          glyphIndex = CharCodeToGlyphIndex(ch);
        }
        this.widths[idx] = GlyphIndexToPdfWidth(glyphIndex);
      }
    }
    public int[] widths;

    public override bool IsBoldFace
    {
      get
      {
        return base.IsBoldFace;
      }
    }

    public override bool IsItalicFace
    {
      get
      {
        return base.IsItalicFace;
      }
    }

    internal int DesignUnitsToPdf(double value)
    {
      return (int)Math.Round(value * 1000.0 / this.fontData.head.unitsPerEm);
    }

    /// <summary>
    /// Maps a unicode to the index of the corresponding glyph.
    /// See OpenType spec "cmap - Character To Glyph Index Mapping Table / Format 4: Segment mapping to delta values"
    /// for details about this a little bit strange looking algorythm.
    /// </summary>
    public int CharCodeToGlyphIndex(char value)
    {
      try
      {
        CMap4 cmap = this.fontData.cmap.cmap4;
        int segCount = cmap.segCountX2 / 2;
        int seg;
        for (seg = 0; seg < segCount; seg++)
        {
          if (value <= cmap.endCount[seg])
            break;
        }
        Debug.Assert(seg < segCount);

        if (value < cmap.startCount[seg])
          return 0;

        if (cmap.idRangeOffs[seg] == 0)
          return (value + cmap.idDelta[seg]) & 0xFFFF;

        int idx = cmap.idRangeOffs[seg] / 2 + (value - cmap.startCount[seg]) - (segCount - seg);
        Debug.Assert(idx >= 0 && idx < cmap.glyphCount);

        if (cmap.glyphIdArray[idx] == 0)
          return 0;
        else
          return (cmap.glyphIdArray[idx] + cmap.idDelta[seg]) & 0xFFFF;
      }
      catch (Exception ex)
      {
        throw ex;
      }
    }

    /// <summary>
    /// Converts the width of a glyph identified by its index to PDF design units.
    /// </summary>
    public int GlyphIndexToPdfWidth(int glyphIndex)
    {
      try
      {
        int numberOfHMetrics = this.fontData.hhea.numberOfHMetrics;
        int unitsPerEm = this.fontData.head.unitsPerEm;

        // glyphIndex >= numberOfHMetrics means the font is mono-spaced and all glyphs have the same width
        if (glyphIndex >= numberOfHMetrics)
          glyphIndex = numberOfHMetrics - 1;

        int width = this.fontData.hmtx.metrics[glyphIndex].advanceWidth;

        // Sometimes the unitsPerEm is 1000, sometimes a power of 2.
        if (unitsPerEm == 1000)
          return width;
        return width * 1000 / unitsPerEm;
      }
      catch (Exception ex)
      {
        throw ex;
      }
    }

    public int PdfWidthFromCharCode(char ch)
    {
      int idx = CharCodeToGlyphIndex(ch);
      int width = GlyphIndexToPdfWidth(idx);
      return width;
    }

#if DEBUTG
    public static void Test()
    {
      Font font = new Font("Times New Roman", 10);
      FontData image = new FontData(font);

//      Font font = new Font("Isabelle", 12);
//      LOGFONT logFont = new LOGFONT();
//      font.ToLogFont(logFont);
//
//      IntPtr hfont = CreateFontIndirect(logFont);
////      IntPtr hfont2 = font.ToHfont();
////      System.Windows.Forms.MessageBox.Show(hfont2.ToString());
//
//      Graphics gfx = Graphics.FromHwnd(IntPtr.Zero);
//      IntPtr hdc = gfx.GetHdc();
//      IntPtr oldFont =  SelectObject(hdc, hfont);
//      int size = GetFontData(hdc, 0, 0, null, 0);
//
//      byte[] fontbits = new byte[size];
//      int xx = GetFontData(hdc, 0, 0, fontbits, size);
//      SelectObject(hdc, oldFont);
//      DeleteObject(hfont);
//      gfx.ReleaseHdc(hdc);
//
//      FontData image = new FontData(fontbits);
//      //image.Read();
//
//
//      //HandleRef
//
//      font.GetType();
    }
#endif
  }
}